The present invention relates to an airbag for protecting a person by rapidly expanding in case of an emergency such as a collision of a high-speed moving body such as a vehicle.
In order to protect an occupant in a car in case of an emergency such as a collision of the car, various airbag devices such as an airbag device for a driver have been used. The airbag device for the driver has an airbag formed by sewing peripheral edge portions of a front panel on the occupant side and a rear panel on the side opposite to the occupant side. An opening for an inflator is provided in the center of the rear panel for receiving a front end of the inflator. The airbag is attached to a retainer around the opening by bolts, pins, rivets or the like. The rear panel has vent holes for venting gas in the airbag to absorb an impact when an occupant on the driver seat plunges into the airbag.
Japanese Patent Publication (KOKAI) No. 01-247242 discloses an airbag in which an inner panel is provided so as to act as a bridge between an opening for an inflator in the rear panel and the front panel, and the inside of the airbag is partitioned into the first chamber disposed at the center of the airbag and the second chamber surrounding the first chamber. The inner panel has a substantially circular shape in a plan view, and an outer peripheral edge portion thereof is connected to a middle portion between the center and the periphery edge of the front panel. The opening for the inflator is provided at the center of the inner panel, and the edge portion of the opening is affixed to a retainer together with the rear panel. The inner panel has communication ports for allowing the first chamber to communicate with the second chamber. Once the inflator is actuated, the first chamber is inflated first, and then the second chamber is inflated. The second chamber is inflated completely later than the first chamber because the gas flows into the second chamber from the first chamber through the communication ports.
It is an object of the present invention to provide an airbag in which the first chamber and the second chamber completely inflate almost at the same time.
Further objects and advantages of the invention will be apparent from the following description of the invention.
According to the present invention, an inside of an airbag is partitioned into a plurality of chambers, and the airbag is inflated by gas from an inflator. The airbag includes a gas-receiving chamber for receiving the gas from the inflator, and communication ports provided so as to supply the gas directly to each of the chambers from the gas-receiving chamber.
In this airbag, when the inflator is actuated, the gas from the inflator is introduced into the gas-receiving chamber first, and is distributed directly to each of the chambers from the gas-receiving chamber (for example, the first chamber and the second chamber) through the communication ports, thereby inflating all chambers substantially at the same time.
According to the present invention, the airbag includes a front panel disposed on a side facing an occupant and a rear panel disposed on a side opposite to the occupant. The front panel and the rear panel are connected at their peripheral edge portions with each other. In this airbag, an opening for the inflator is provided at the center of the rear panel. An inner panel is provided to divide the inside of the airbag into a central first chamber and the second chamber surrounding the first chamber. An opening is provided at the center of the inner panel as a substantially concentric circle relative to the opening of the rear panel. A peripheral edge portion of the inner panel is connected to an intermediate portion between the central portion and a peripheral edge portion of the front panel. A partition panel is attached to the inner panel for dividing the inside of the first chamber, thereby forming the gas-receiving chamber on a side of the opening for the inflator. The partition panel is provided with communication ports for connecting the gas-receiving chamber to the first chamber. Further, the inner panel is provided with communication ports for connecting the gas-receiving chamber to the second chamber.
In the airbag, since the front panel is connected to the edge portion of the opening for the inflator via the inner panel, the connection between the front panel and the opening for the inflator is significantly strong.
According to another aspect of the present invention, an airbag includes a front panel disposed on a side facing an occupant and a rear panel disposed on a side opposite to the occupant. The front panel and the rear panel are connected at their peripheral edge portions with each other. In this airbag, an opening for the inflator is provided at the center of the rear panel. An inner panel is provided to divide the inside of the airbag into the first chamber disposed at the center of the airbag and the second chamber surrounding the first chamber. A partition panel is provided to form a gas-receiving chamber between the inner panel and the opening for the inflator. An opening is provided at the center of the partition panel as a substantially concentric circle with the opening of the rear panel. A peripheral edge portion of the partition panel is connected to an intermediate portion between the central portion and a peripheral edge portion of the inner panel. The inner panel is provided with communication ports for connecting the gas-receiving chamber to the first chamber. Further, the partition panel is provided with communication ports for connecting the gas-receiving chamber to the second chamber.
In the airbag, through strong connection between the partition panel and the inner panel, it is possible to attach the front panel strongly to the edge portion of the opening for the inflator in the rear panel.
According to still another aspect of the present invention, an airbag includes a front panel disposed on a side facing an occupant and a rear panel disposed on a side opposite to the occupant. The front panel and the rear panel are connected at their peripheral edge portions with each other. In this airbag, an opening for the inflator is provided at the center of the rear panel. An inner panel is provided to divide the inside of the airbag into the first chamber disposed at the center of the airbag and the second chamber surrounding the first chamber. A cylindrical partition panel is provided, and the inside of the cylindrical partition panel is formed as a gas-receiving chamber. The partition panel has an opening disposed substantially concentrically with the opening of the rear panel. A peripheral edge portion of the inner panel is connected to the front panel, and the central portion of the inner panel is connected to the partition panel. Communication ports for allowing the first chamber to communicate with the gas-receiving chamber are provided in each of the inner panel and the partition panel, and end portions of the cylindrical partition panel constitute communication ports for allowing the gas-receiving chamber to communicate with the second chamber.
In this airbag, the gas can be ejected to the second chamber from the cylindrical partition panel in a longitudinal direction of the cylinder, thereby allowing the second chamber to be rapidly inflated in an expanding direction of the airbag.
According to the present invention, the airbag may be arranged such that vent holes are provided in the rear panel, and the inner vent holes for connecting the first chamber to the second chamber are provided in the inner panel. When the occupant plunges into the first chamber, the gas in the first chamber flows into the second chamber through the inner vent holes, and then the gas flows out from the vent holes, thereby absorbing an impact.